Telephone-exchange system.



E. E. HINRICHS EN. TELEPHONE EXCHANGE SYSTEM. APPLICATION FILED MAY 22, 1917.

1,276,761. Patented Aug. 27, 191&

T00 erY. rel et 1 UNITED S ENT curios.

EDWARD E. HINEIcnsEN, or NEW YORK, N. Y., AssienoE T0 WESTERN ELEc'rEIc COM- PANY, INCORPORATED, or NEW our; iv. n, a conrona'rro v or NEW YORK.

TELElH-IONE-EXCHANGE sY-s'rEM.

To, all whom it may concern:

Be it known that I, lilnnn-mn E. HINRIOH- SEN, a citizen ofthe United States,-residing at New York, in the county of New York and State ofNew York, have invented cer tain new and useful Improvements in Telehone-Exchange Systems. of which the fol-f ing supervisory signaling-device of a link.

circuitconnected with a telephone line as a called line operates continuously as a ringing signal and later operates intermittently as a disconnect signal. 4

By the embodiment of these features in a system the same character of signal is always presented to an operator when an act upon her part for the benefit of the subscriber is called for,-whi1e, when an act which is not for the benefit of the subscriber is called for, a signal of a different character or manifestation is furnished. In this way the possibility of confusion in interpreting signals is avoided.

For a more complete understanding of this invention, reference should be had to the following description taken in connection with the accompanying drawing, where in there are shown two telephone lines A and B extending from subscribers stations and terminating at a central office at which is located a link or cord circuit C containing one embodiment of this invention, and employed for interconnecting the telephone lines. It is thought that the nature of this invention is such that a proper understanding thereof will be had from a description ofthe operation of the system shown in the drawing; hence it will be so described.

Subscriber A in initiatin a call in the usual manner causes the lighting of line lamp 5, and the operator upon observing the lighted condition thereof inserts answering plug 35 of the cord circuit into line jack 7. Thereupon answering supervisory lamp 37 light relay 36 and cut-01f rel y 6 p rspecificationof letters Patent. Patented Aug. 27, 191 8. Application filed May 22, 1917. Serial No. 170,308.

. ate over a circuit from battery through the lamp 37 left-hand winding of relay 36, sleeve contacts of the answering plug 35 andline jack 7, and the winding of cut-oil relay 6 to ground. The lighted condition of the-answering supervisory lamp 37 is an indication to the operator that the cord circuit is connected with the line of a calling subscriber and'that this call has not been attended to. This,of course, calls for anact upon the part of the operator for the benefit of the subscriber. The energization of answering supervisory. relay 38 also resulted from the insertion of the answering plug 35 into the link jack 7. i

The operator may now actuate'listening key 39 to connect the operators telephone set to the cord circuit, and, in so doing, closesfa contact 40, whichestablishes a circuit through right-hand winding, of relay 36 in parallel with the lamp 37. The windings of relay 36 are differentially connected so that, upon the establishment of this circuit through its righthand winding the relay'is deenergized, releasing its ,armatures, thereby establishing a maintaining circuit through its right-hand winding which includes the right-hand normal contact of relay 36 and the alternate contact of supervisory relay 38. Since the right-hand windmains eft'aced until the answering supervisory relay 38 is dcenergized and relay 36 energized.

The operator may, upon being advised of the number of the line with which connection is desired and assuming it to be line B, restore the listening key to normal posi tion, and insert the calling plug 45 into line jack 42 of line B, whereupon calling supervisory lamp 47 is lighted and cutofl? relay 44 operated. The subscriber on the line'B may now be signaled by actuating a ringing key 41. In response, the called subscriber removes the receiver from the switchhook and causes the operation of callingv supervisory relay 48, which connects the left-hand winding ofa relay 46 in parallel with the lamp 4 thereby efiacing the lamp. The establishment of the circuit through lefth'and winding of relay 46 causes the operation of this relay, which, in operating, completes a locking circuit for itself, which 'may be traced from battery through the Z ing of relay 36 is connected in parallel with cluding theright-hand winding of relay 36,

which, thereupon, due to a flow of current through its left-hand winding, attracts its armatures, connecting interrupter 50 and resistance 51 in parallel with the answering supervisory lamp 37. Due to the rotation of the interrupter 50, the lamp is intermittently shunted, thereby causing the intermittent lighting of the lamp to furnish a disconnect signal. This path, in parallel with the lamp 37, may be traced from batterythrough interrupter 50, resistance 51, left-hand alternate contact of relay 36, normal contact of relay 38 to the upper terminal of the lamp. The deenergization of the calling supervisory relay 48 connects interrupter 50 and resistance 52 in parallel with the lamp 47, thereby causing the intermittent lighting of the calling supervisory lamp to furnish a disconnect signal.

The operator, in response thereto, mayv withdraw the plugs from the jacks, restor ing all apparatus to normal condition.

However, should the calling subscriber,

before the plugs are withdrawn from the jacks, remove the receiver from the switchhook to initiate another call, the resulting energization of the answering supervisory relay 38 disconnects resistance 51 and inter rupter 50 from circuit relation with the lamp 37, thereby permitting the answering supervisory lamp to be lighted continuously to furnish a recall signal to the operator. In response to this signal, the operator may actuate listening key 39, causing the deenergization of relay 36, as before described. The connection may then be completed with the line desired by first with drawing the calling plug from line jack 42, thereby denergizing relay 46 and eflacing calling supervisory lamp 47, and then inserting the calling plug into the jack of the desired line.

What is claimed is:

1. A telephone exchange system comprising a telephone line, a link circuit, a signaling device in the link circuit, a supervisory relay and a secondary relay in the link circuit energized upon connection of the link circuit with the line as a calling line, an opcrating circuit for the signaling device established upon the energization of both relays, an operator-controlled switch actuated to cause the deenergiza-tion of this second; ary relay to disablethe operating circuit of the signaling device, and interrupter mechanism brought into circuit with the signaling device-upon the subsequent deenergization of the supervisory relay and the energization of the secondary relay.

2. A telephone exchange system comprising a telephone line, a link circuit, a signaling device in the link circuit, a supervisory relay and a secondary relay in the link circuit energized upon connection of the link circuit with theline as a calling line, an operating circuitfor the signaling device established upon the energization of both relays, an operator-controlled switch actuated to cause the deen'ergization ofthis secondary relay, a shunt circuit for the signaling device established upon the deenergization of the secondary relay while the supervisory relay is energized, and an relays, an operators telephone set, a switch.

for connecting the operators telephone set with the link circuit and when actuated causing the deenergization of the secondary relay, a shunt circuit for the signaling device established upon the denergization of the secondary relay while the supervisory relay is energized, an interrupter mechanism included 1n a shunt circuit of the signaling device upon the subsequent deen,

ergization of the supervisory relay followed by the energization of the secondary relay.

4. A telephone exchange system comprising a telephonev line, a link circuit, a sig inaling device in the link circuit, a supervisory relay and a secondary relay in the link circuit energized upon connection of the link circuit with the line as a calling line, an operating circuit for the signaling,

device established upon the energization of both relays, an operator-controlled switch actuated to cause the deenergization of the secondary relay, a shunt circuit for the sig-.

naling device established upon the denergization of the secondary relay while the supervisory relay is energized, and another shunt circuit for the signaling device including interrupter mechanism and contacts of both relays established upon the deenergization ofthe supervisory relay followed by the energization of the secondary relayto cause the intermittent operation of the signaling device. J H

5; A telephone exchange system comprising a telephone line, a link circuit, a signaling device in :thelink circuit, a supervisory relay and a secondary relay in the link circuit energized upon connection of the link circuit with the line as a calling line,an operating circuit for the signaling device established upon the energization of both relays, an operators telephone set, a switch for connecting the operators telephone set with the link circuit and when actuated causing the deenergization of the secondary relay, a shunt circuit for the sig naling device established upon the deenergization of the secondary relay while the supervisory relay is energized, and another shunt circuit for the signaling device ineluding interrupter mechanism and contacts of both relays established upon the deenergization of the supervisory relay followed by the energization of the secondary relay to cause the intermittent operation of the signaling device.

6. A telephone exchange system comprising a telephoneline, a link circuit, a signaling device in the link circuit, a supervisory relay and a secondary relay in the link circuit energized upon connection of the link circuit with the line as a calling line, an operator-controlled switch actuated to de'energize the secondary relay, interrupter mechanism included in circuit with the signaling device upon the deenergization of the supervisory relay followed by the energization of a secondary relay to cause the intermittent operation of the signaling device to furnish a disconnect signal, and an operating circuit for the signaling device rendered efiective upon the subsequent energization of the supervisory relay to cause the continuous operation of the signaling device to furnish a recall signal. a

7. A telephone exchange system comprising a telephone line, a link c1rcuit,-a signal ing device in the link circuit, a supervisory relay and a secondary relay in the link circuit energized upon connection of the link circuit with the line as a calling line, an operator-controlled switch actuated to deenergize the secondary relay, a shunt circuit including interrupter mechanism established for the signaling device upon the denergization of the supervisory relay followed by the energization of the secondary relay to cause the intermittent operation of the signaling device to furnish a disconnect signal, and an operating circuit for the signaling device rendered effective upon the subsequent energization of the supervisory relay to cause the continuous operation of thesignaling'device to furnish a recall sig nal. I a

8. A telephone exchange system comprising a telephone line, alink circuit, a signaling'device in the link circuit, a supervisory relay and a secondary relay in the link circuitenergized upon connection of the link circuit with. the line as a calling line, an operator-controlled switch actuated to deenergize the secondary relay, an intermittently closed operating circuit for the signaling device established upon the denergizati'on of the supervisory relay followed by the energization of the secondary relay to cause the intermittent operation of the signaling device to furnish a disconnect signal, and an operating circuit for the signaling device rendered effective upon the subsequent energization of the supervisory relay to cause the continuous operation of the signaling device to furnish a recall signal.

9. A telephone exchange system comprising a telephone line, a link circuit, a signaling device in the link circuit, a supervisory relay and a secondary relay in the link circuit energized upon connection of the link circuit with the line as a calling line, an operator-controlled switch actuated to deenergize the secondary relay, an intermittently closed operating circuit for the signaling device including contacts of both relays established upon the denergization of the snpervisory relay followed by the energization of the secondary relay to cause the intermittent operation of the signaling device to furnish a disconnect signal, and an I operating circuit for the signaling device rendered effective upon the subsequent energization of the supervisory relay to cause the continuous operation of the signaling device to furnish a recall signal.

10. A telephone exchange system comprising a telephone line, a linkcircuit, a signaling device in the link circuit, an operating circuit for the signaling device established upon the connection of the link circuit with the line as a called line to cause the continuous operation of the signaling device, a supervisory relay in the link circuit, a secondary relay energized upon the energization of the sunervisoryrelay, a shunt circuit for the signaling device including a winding of the secondary relay established upon the energization of the supervisory relay to disable the signaling device, and a second shunt circuit including interrupter mechanism substituted for the first-mentioned shunt circuit upon the subsequent deenergization of the supervisory relay to cause the intermittent operation of the signaling device.

11. A telephone exchange system comprising a telephone line, a link circuit, a signaling device in the link circuit, an operating circuit for he s g al ng device establi h d circuit for the signaling device established upon the energization of the supervisory relay to disable the signaling device, a second ary relay energized by the establishment of the shunt circuit, a locking circuit for the 10 secondary relay established upon the ener= -Gop1es of this patent may be obtained for gization thereof, and a second shunt circuit including interrupter mechanism substituted for the first-mentioned shunt circuit upon the subsequent deenergization of the supervisory relay to cause the intermittent operation of the signaling device.

In Witness whereof, I hereunto subscribe my name this 18th day of May, A. D., 1917.

EDWARD E. HINRICHSEN.

five cents each, by addressing the Commissioner of Patents, Washington, D. 0. 

